projector.h File Reference

#include "include.h"
#include "parameters.h"
#include "color.h"

Go to the source code of this file.

Functions
void	projector_init (void)
	Initialize projector peripherals, variables etc. MUST be called before calling any other projector functions! More...
void	projector_set_pixel (struct color const color, unsigned int x, unsigned int y)
	Set the color of a pixel at the specified location. More...

Function Documentation

projector_init()

void projector_init

(

void

)

Initialize projector peripherals, variables etc. MUST be called before calling any other projector functions!

Definition at line 123 of file projector.c.

                      {
  /* Set Up Pixel CLock */

  // Open Timer1 with the following configuration:
  //  - T1_ON         :: Timer is turned on
  //  - T1_SOURCE_INT :: Clock source is internal
  //  - T1_PS_1_1     :: Prescalar is 1 to 1 (timer sees PBCLK)
  //
  // The timer's period is used to fine-tune how long each pixel lasts;
  // one pixel displayed every time the timer wraps around.
  OpenTimer1(T1_ON | T1_SOURCE_INT | T1_PS_1_1, PIXEL_ON_TIME);

  // set up the pin to reset the Gate Latch, set initially high
  // (the signal is active low)
  PORTSetPinsDigitalOut(IOPORT_A, BIT_3);
  mPORTASetBits(BIT_3);

  /* Set Up CN  */

  // see reference manual 12.3.3.1
  CNCONASET = BIT_15; // enable CN on Port A (set bit 15 of CNCON to 1)
  PORTSetPinsDigitalIn(IOPORT_A, BIT_4); // RA4 is input
  unsigned int ignore = PORTA; // clear interrupt
  IPC8SET  = ((unsigned int) 5) << 18; // set CN interrupt priority
                                       // (IPC6<20:18>=5, defaults to 0 at POR)
  IFS1CLR  = BIT_13; // clear CN interrupt flag (set bit 0 of IFS1 to 0)
  CNENASET = BIT_4;  // enable for RA4 (set bit 4 of CNENA to 1)
                     // see family data sheet 11.1.4
  IEC1SET  = BIT_13; // enable CN interrupt (set bit 0 of IEC1 to 1)

  /* Set Up DMA */

  // Set up the pins as an output
  PORTSetPinsDigitalOut(IOPORT_B, BIT_0 | BIT_1   // red
                                | BIT_2 | BIT_3   // blue
                                | BIT_4 | BIT_5); // green

  // Configure DMA interrupt vector and enable DMA interrupts on CPU
  INTSetVectorPriority(INT_VECTOR_DMA(PIXEL_DMA_CHN), INT_PRIORITY_LEVEL_5);
  INTSetVectorSubPriority(INT_VECTOR_DMA(PIXEL_DMA_CHN),
                          INT_SUB_PRIORITY_LEVEL_3);
  INTEnable(INT_SOURCE_DMA(PIXEL_DMA_CHN), INT_ENABLED);

  configure_dma_for_row(0);

  /* Set Up SPI */

  // SPI Slave Sync output on pin 26
  PPSOutput(1, RPB15, SS1);

  // SPI1 data output on pin 17
  PPSOutput(2, RPB8, SDO1);

  // SPI channel 1 channel A drives the y axis control mirror.
  // The messages we send are 16 bits long (4 control bits, 12 signal bits).
  // The config flags do the following:
  //  - SPICON_MSTEN  :: Set to master mode
  //  - SPICON_MODE16 :: Sets the word size to 16 bits
  //  - SPICON_ON     :: Module ON Control
  //  - SPICON_FRMPOL :: Polarity of frame signal
  //  - SPICON_CKP    :: Reverse clock edges
  //  - SPICON_FRMEN  :: Use automatic framing: Serial clock is always on
  //                     even when no data is being sent and Slave Select/CS
  //                     pulses before each word
  // The fpbDiv = 2 sets baud rate to Fpb / fpbDiv.
  SpiChnOpen(Y_MIRROR_SPI_CHN, SPICON_MSTEN | SPICON_MODE16 | SPICON_ON
             | SPICON_FRMPOL | SPICON_CKP | SPICON_FRMEN, 2);
}

projector_set_pixel()

void projector_set_pixel	(	struct color const	color,
		unsigned int	x,
		unsigned int	y
	)

Set the color of a pixel at the specified location.

Once a pixels value is changed, the new value will be projected the next time the pixel is output (there is no v-sync).

Parameters

color	Color to be displayed
x	Number of pixels from left side
y	Number of pixels from the top

Definition at line 205 of file projector.c.

                                                         {
  projector_framebuffer[y][x + RED_PHASE_SHIFT  ].red   = color.red;
  projector_framebuffer[y][x + GREEN_PHASE_SHIFT].green = color.green;
  projector_framebuffer[y][x + BLUE_PHASE_SHIFT ].blue  = color.blue;
}